Luminescence is often used in biological assays as a measure of the activity of a reporter molecule. The reporter molecule, in turn, links the luminescent measurement to a biological process of interest such as transcription (gene expression), translation (protein expression), protein-protein interactions, and so forth, thereby allowing for quantitative measurements of changes occurring in the biological process.
The reporter molecule is typically a luminogenic enzyme (e.g., firefly luciferase, Renilla luciferase, Oplophorus luciferase, etc.) that, when provided with its luminogenic substrate, results in the production of light, i.e., luminescence. The luminogenic substrate, however, can decompose during storage thereby resulting in loss of the substrate before addition to or use in the biological assay. Such decomposition can be the result of instability of the luminogenic substrate in solution over time in a temperature-dependent manner. This decomposition results in waste of the luminogenic substrate and reduced sensitivity and reproducibility of luminescent measurements derived from biological assays that employed the decomposed luminogenic substrate. Additionally, the products from this decomposition often inhibit the luminescent reaction.
Accordingly, the need exists for the identification and development of new compositions and/or methods for stabilizing a luminogenic substrate prior to its use in a luminescent reaction.